In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does ...In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.展开更多
The object oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems. In the research on the rapid construction of Structured Development Envi- ronm...The object oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems. In the research on the rapid construction of Structured Development Envi- ronment (SDE)that supports detailed design and coding in software development, a generator that can gener- ate the SDE has been applied as a metatool. The kernel of SDE is a syntax-directed editor based on the ob- ject-oriented concepts. The key issue in the design of SDE is how to represent the elements of target language with the class concept and a program internally. In this paper, the key concepts and design of the SDE and its generator as well as the implementation of a prototype are to be discussed.展开更多
文摘In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.
文摘The object oriented software development is a kind of promising software methodology and leading to a wholly new way for solving problems. In the research on the rapid construction of Structured Development Envi- ronment (SDE)that supports detailed design and coding in software development, a generator that can gener- ate the SDE has been applied as a metatool. The kernel of SDE is a syntax-directed editor based on the ob- ject-oriented concepts. The key issue in the design of SDE is how to represent the elements of target language with the class concept and a program internally. In this paper, the key concepts and design of the SDE and its generator as well as the implementation of a prototype are to be discussed.
